<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>JS/CSS实现提示弹窗</title>
    <style>
        /* Popup container - can be anything you want */
        .popup {
            position: relative;
            display: inline-block;
        }
        .popup .popuptext {
            visibility: hidden;
            width: 160px;
            background-color: #555;
            color: #fff;
            text-align: center;
            border-radius: 6px;
            padding: 8px 0;
            position: absolute;
            z-index: 1;
            bottom: 125%;
            left: 50%;
            margin-left: -80px;
        }
        .popup .popuptext::after {
            content: "";
            position: absolute;
            top: 100%;
            left: 50%;
            margin-left: -5px;
            border-width: 5px;
            border-style: solid;
            border-color: #555 transparent transparent transparent;
        }
        .popup .show {
            visibility: visible;
            -webkit-animation: fadeIn 1s;
            animation: fadeIn 1s;
        }
    </style>
</head>

<body style="text-align:center">
    <h2>弹窗</h2>
    <div class="popup" onclick="myFunction()">点我有弹窗!
        <span class="popuptext" id="myPopup">提示信息!</span>
    </div>
    <script>
        function myFunction() {
            var popup = document.getElementById("myPopup");
            popup.classList.toggle("show");
        }
    </script>
</body>

</html>